Using a form to update the same page - all in php and other veriables

[dave007]

I have xml files for a whole bunch of data. I have managed to get them into a nice format and showing on an html page fine. I can even go backwards and forwards between xml files. To do this I simply use a $_GET['rec'] variable.

 

However, I've been trying to ALSO have things update on the page when the user selects (preferably just clicks on) an item in a <select> tag - populated from the XML file.

 

Below is my latest attempt at this (with the population of the <select>):

 

echo "<form id=v2p method=\"POST\"><select size = 5 onclick=\"javascript:document.v2p.submit();return false;\">";

 

$vars = $xmlDoc->getElementsByTagName('var');

foreach($vars as $var)

{

$varname = $var->getElementsByTagName('vaname')->item(0)->nodeValue;

echo "<option value=$varname>$varname</option>";

}

echo "</select></form>";

echo "<br/>";

$var2plot = $_POST['v2p'];

echo "<a>$var2plot</a>";

 

I get an "Undefined index: v2p" error on line 75 ($var2plot = $_POST['v2p']; ):

 

Please could someone show me a nice way to make it work...

 

Thanks in advance,

Dave

[JonnoTheDev]

The POST array uses field NAMES for its indexes you haven't defined any i.e.

// $_POST['v2p'] will contain the value of the following field after form submission i.e. 123
<input type="text" name="v2p" id="xyz" value="123" />

[dave007]

I think this is a problem with sending two GET requests... I've managed to make the form update one of the

<form name="VarForm" action="' . $_SERVER['PHP_SELF'] . '" method="GET"><select name = "v2p" size=5 OnChange="VarForm.submit();">';

 

but now the 'rec' variable is lost... please could someone save my hair from all being pulled out.

 

Thanks

[dave007]

Is there any way to keep the other vraiable?

[JonnoTheDev]

Is there any way to keep the other vraiable?

Keep persistent with any of the following:

 

1. A session variable

2. A hidden field for post / get

3. A url parameter